The disappointing finding was presented April 2 at the American Academy of Neurology's annual meeting in Honolulu.
University of Texas Health Science Center researcher Dr. David G. Sherman tracked stroke events of 4,060 people with heart rhythm disorder who were enrolled in the six-year Atrial Fibrillation Follow-Up Investigation of Rhythm Management (AFFIRM) study.
The study found that 8.9 percent of the people in AFFIRM taking anti-arrhythmic drugs (meant to restore normal heart rhythm) had strokes, compared to 7.4 percent of the people taking a simpler alternative therapy called rate regulation. Both groups of patients took the blood-thinning drug warfarin.
"While the trial confirmed that use of warfarin, an anticoagulant, reduces the risk of stroke by almost 70 percent, aggressive efforts to control atrial fibrillation did not seem to have nearly as beneficial an effect," Sherman says in a news release.
Here's where you can learn more about atrial fibrillation.